#ifndef __DAY07_HOMEWORK_H_
#define __DAY07_HOMEWORK_H_
#include <iostream>
#include <cmath>
using namespace std;
class graph
{
public:
    graph();
    virtual ~graph();

public:
    virtual double perimeter() = 0;
    virtual double area() = 0;
};
class rectangle : graph
{
public:
    rectangle(float, float);
    ~rectangle();

public:
    double perimeter();
    double area();

private:
    float lenth;
    float wide;
};

class triangle : graph
{
public:
    triangle(float, float);
    ~triangle();

public:
    double perimeter();
    double area();

private:
    float bottom;
    float height;
};
class circle : graph
{
public:
    circle(float);
    ~circle();

public:
    double perimeter();
    double area();

private:
    float radius;
    const float PAI = 3.14159;
};

#endif
